Linear drive without a piston rod

Abstract

A linear drive without a piston rod, which has a laterally slotted guide tube closed on the end faces and a piston mounted so as to be slidably displaceable therein, is provided with a sealing band and with separate profile elements engaging the sealing band. The sealing band extends from one end of the guide tube along its longitudinal slot to its other end. In order to hold the sealing band in the longitudinal slot, separate profile elements are arranged in the longitudinal slot. The profile elements cause the sealing band to engage the guide tube.

What is claimed is: 
     
       1. A linear drive, comprising: a guide tube having a longitudinal slot defined therein by at least one flank, and at least one closing device for closing an end face of the guide tube;   a piston mounted in the guide tube and displaceable in a longitudinal direction;   a web connected to the piston and passing through the longitudinal slot;   a sealing band for sealing the longitudinal slot at least in pressurized regions and which is held fixedly at end faces relative to the guide tube, at least one portion of the sealing band being seated in the longitudinal slot; and   at least one separate profile element disposed in the longitudinal slot and extending essentially along a longitudinal extension of the flank of the longitudinal slot;   wherein the profile element is connected to the sealing band such that a catching connection is formed between the sealing band and the guide tube.   
     
     
       2. The linear drive as claimed in claim 1, wherein the profile element is connected to the flank. 
     
     
       3. The linear drive as claimed in claim 1 wherein the flank of the longitudinal slot includes at least one groove and wherein the profile element includes a portion seated in the groove. 
     
     
       4. The linear drive as claimed in claim 1, wherein a side of the sealing band facing the flank of the longitudinal slot includes a longitudinal recess extending over an entire length of the sealing band. 
     
     
       5. The linear drive as claimed in claim 4, wherein the profile element includes a catch portion which extends into the longitudinal recess. 
     
     
       6. The linear drive as claimed in claim 5, wherein the catch portion is held resiliently in a direction toward the flank. 
     
     
       7. The linear drive as claimed in claim 3, wherein the profile element has an oval cross-section. 
     
     
       8. The linear drive as claimed in claim 7, wherein the groove has a rectangular cross-section. 
     
     
       9. The linear drive as claimed in claim 8, wherein flat sides of the profile element bear on mutually parallel side walls of the groove and wherein the profile element includes a round catch portion which projects into the longitudinal slot. 
     
     
       10. The linear drive as claimed in claim 1, wherein the profile element is made from sponge rubber. 
     
     
       11. The linear drive as claimed in claim 1, wherein the profile element is a thin-walled flexible plastic hose. 
     
     
       12. The linear drive as claimed in claim 1, wherein the profile element is connected to the flank by adhesive. 
     
     
       13. The linear drive as claimed in claim 3, wherein the profile element is mounted in the groove resiliently in relation to a direction away from the sealing band. 
     
     
       14. The linear drive as claimed in claim 3, wherein the portion of the profile element seated in the groove includes spring means. 
     
     
       15. The linear drive as claimed in claim 14, wherein the spring means are legs supported on the groove. 
     
     
       16. The linear drive as claimed in claim 15, wherein the legs extend over an entire length of the profile element. 
     
     
       17. The linear drive as claimed in claim 15, wherein the legs bear on bearing faces in the groove, the bearing faces form an angle that opens toward the flank, and the legs are pretensioned resiliently in a direction toward the bearing faces. 
     
     
       18. The linear drive as claimed in claim 3, wherein the profile element includes a catch portion in the form of a resilient tongue or lip wherein the catch portion is disposed between the flank and the sealing band and is connected to the portion of the profile element seated in the groove. 
     
     
       19. The linear drive as claimed in claim 1, wherein the flank includes two grooves and the profile element includes two portions seated in the two grooves, respectively. 
     
     
       20. The linear drive as claimed in claim 1, wherein the profile element completely covers the flank. 
     
     
       21. The linear drive as claimed in claim 1, wherein the profile element includes at least one portion which bears fixedly on the flank and which is raised in relation to the flank.